The present invention relates to a sub-band coding/decoding circuit for video signal band and for use in an Advanced-TV (hereinafter, referred to as A-TV) and a method thereof, and particularly to a sub-band coding/decoding circuit and method thereof, for dividing the video signal into 9 bands by coding 3.times.3 sub-bands in order to transmit 6 bands of the 9 bands and then for synthesizing in an inverse sequence the signals transmitted in the divided form.
Generally, the video signal band for A-TV is much wider than the range of the conventional 6 MHz band, and the picture of A-TV consists of 1000 vertical lines or more and 1200 horizontal samples or so. Because of this fact, the conventional TV can not receive the band signal of A-TV.